共查询到20条相似文献，搜索用时 15 毫秒
1.
Margaret G. Fox 《Research quarterly for exercise and sport》2013,84(4):327-328
Abstract A screening test for lateral dominance was administered to 167 college women. Twenty-six showed left dominance. Of this group four were taught to bowl left-handed, six were eliminated from the study for various reasons and 16 were taught to use their preferred hand, the right. All 20 subjects preferred using their right hand. Both groups were equated as to the amount of practice and motor ability. The group using the presumably dominant left hand were significantly poorer in their bowling average than the group which, though demonstrating left dominance, were permitted to bowl with their preferred hand. 相似文献
2.
Abstract The relative length of the second and fourth digits (2D:4D) is a putative marker for prenatal testosterone. Low 2D:4D has been reported to correlate with high performance in sport in general. Here, for the first time, we examine the relationship between 2D:4D and performance in elite rugby players. The 44 players (28 forwards, 16 backs) were drawn from the Ospreys Rugby Union Club and 44 age-matched controls. The measures of performance comprised age-adjusted number of international performances (caps) for Wales, a comparison of coaches' first-choice League team with others, and the number of tries scored by backs in club matches. Compared with controls, players were larger and had lower 2D:4D for the right and left hand. With regard to number of caps, players with low 2D:4D in their right hand and low right 2D:4D compared with their left (right ? left 2D:4D difference) had high numbers of caps. First-choice players did not differ significantly from second-choice players in their 2D:4D but they did have a lower right ? left 2D:4D difference than second-choice players. Low right 2D:4D and low right ? left 2D:4D difference were significantly linked with large numbers of tries. We conclude that low right 2D:4D and low right ? left 2D:4D difference are predictors of high rugby performance. 相似文献
3.
《European Journal of Sport Science》2013,13(3):171-175
Abstract Central fatigue refers to a progressive decline in the ability to activate muscles voluntarily. Although fatigue-related inhibitory input to the motor cortex from group III and IV afferents that carry sensory information is thought to contribute to the fatigue-related changes in the motor cortex, other sites effectively driving the motor cortex during physical fatigue have not been identified. Contribution of a mirror visual feedback system to regulate physical fatigue was examined. The study group consisted of 12 healthy participants who performed 60 repetitive left handgrips at maximal voluntary contraction every 1 s as a fatigue-inducing physical task session. Before and after the session, left and right handgrip forces were measured for fatigue evaluation. After the fatigue-inducing task session, handgrip forces of the right and left hands were reduced. Although there was no difference in the reduced level of the handgrip force of the right hand between the sessions with and without a Ramachandran's mirror box, that of the left hand was attenuated by watching the mirror of the mirror box. A mirror visual feedback system is involved in the mechanisms regulating physical fatigue. 相似文献
4.
Abstract Although the effects of lateral biases in visual attention (“pseudoneglect”) have been examined in real-world settings, this phenomenon has yet to be considered within the realm of sporting performance. In the present study, we investigated the effects of pseudoneglect on putting errors in golf. Novice golfers (n = 30) performed 90 putting trials followed by a series of pseudoneglect tasks: requiring participants to bisect lines manually and with a biomechanical bisection tool. All pseudoneglect measures were performed with both the left and right hands. Results demonstrated a leftward bias for all the pseudoneglect tasks, and a rightward bias for putting error. Moreover, the results revealed that individuals who bisected lines to the left on the Bisection Tool (the typical class of pseudoneglect error for humans) with the left hand (the hand that typically produces the greatest pseudoneglect bias) displayed significantly smaller rightward putting errors. Moreover, these individuals also holed more putts. No other pseudoneglect tasks were shown to impact on putting performance. Our findings suggest that lateralized attentional biases have a significant effect on sport performance; they appear to influence a wide range of precision-based sports (e.g. shooting, archery). Findings are also discussed in terms of the processes that are likely to be involved in this effect. 相似文献
5.
Theresa Anderson 《Research quarterly for exercise and sport》2013,84(4):532-537
Abstract The effect of actively warming the forearm musculature on dynamic grip endurance was investigated by comparing the performance of the left and right hands, with or without warming-up, on a spring-loaded grip ergometer. There were 21 male subjects, aged 19 to 23. Warming-up consisted of 9 min. of four hand and wrist exercises conducted in 30-sec. bouts, at a rate of one repetition per sec., with 15-sec. intervals between bouts. This warm-up was shown to lead to temperature increases of between 1.6 C and 2.6 C in the flexor digitorum sublimis muscles of five subjects. Warming-up had no effect on grip endurance. 相似文献
6.
《运动与健康科学(英文)》2014,3(4):333-337
BackgroundProlonged sitting is a risk factor for low-back pain. The primary purpose of this study is to determine if prolonged active sitting will result in increased trunk motion.MethodsFifteen healthy female participants volunteered to sit for 30 min on each of three surfaces including an air-cushion, a stability ball, and a hard surface. Trunk motion was monitored using a Vicon motion capture system, and foot center of pressure was collected with two AMTI force plates.ResultsOur findings indicated that the average speed of the trunk center of mass significantly increased with seating surface compliance. There were significant differences in right and left foot centers of pressure in the antero-posterior direction between the ball and air-cushion conditions and the ball and chair conditions.ConclusionActive sitting results in increased trunk motion and could have a positive effect on low-back health. 相似文献
7.
John C. Bachman 《Research quarterly for exercise and sport》2013,84(3):220-222
Abstract To determine the relationship between the extension power of the arms and power of the legs, 26 male Macalester College students were tested on a modified Biokinetic Swim Bench. All measurements were measured accurately and reliably. Correlations between individual abilities on the leg extension and the arm extension tasks are low, r =.194. Between the right arm and the right leg the r = .041; and between the left arm and the left leg the r = .227. These correlations are not significant. It was concluded that extension power abilities are highly specific in nature and that assuming arm power from a leg power measurement is not a viable alternative to actual measurement of the arm power. 相似文献
8.
The relative length of the second and fourth digits (2D:4D) is a putative marker for prenatal testosterone. Low 2D:4D has been reported to correlate with high performance in sport in general. Here, for the first time, we examine the relationship between 2D:4D and performance in elite rugby players. The 44 players (28 forwards, 16 backs) were drawn from the Ospreys Rugby Union Club and 44 age-matched controls. The measures of performance comprised age-adjusted number of international performances (caps) for Wales, a comparison of coaches' first-choice League team with others, and the number of tries scored by backs in club matches. Compared with controls, players were larger and had lower 2D:4D for the right and left hand. With regard to number of caps, players with low 2D:4D in their right hand and low right 2D:4D compared with their left (right?-?left 2D:4D difference) had high numbers of caps. First-choice players did not differ significantly from second-choice players in their 2D:4D but they did have a lower right?-?left 2D:4D difference than second-choice players. Low right 2D:4D and low right?-?left 2D:4D difference were significantly linked with large numbers of tries. We conclude that low right 2D:4D and low right?-?left 2D:4D difference are predictors of high rugby performance. 相似文献
9.
Stanley P. Sady Mark P. Savage Wade H. Thomson Marlene M. Petratis 《Research quarterly for exercise and sport》2013,84(3):302-304
Abstract When subjects make simultaneous aiming movements of the upper limbs over different distances, assimilation effects are shown; the shorter distance limb overshoots when paired with a longer distance limb. However, it is not known whether assimilation effects are due to variations in distance per se or to variations in target location. To separate the possible influences of distance and location, 60 subjects made rapid bimanual aiming movements in one of four conditions. The two different-distance groups made a 20° movement in the left hand and a 60° movement in the right hand to either the same or different target locations. The comparison groups moved 20° in each limb. Somewhat surprisingly, spatial assimilations were greater when moving different distances to the same, rather than different, target locations, which suggests interlimb differences in distance mediate assimilation effects rather than target location. Temporal assimilations were greater when distance and location were varied, but the assimilations were not related to interlimb differences in velocity, as predicted by Marteniuk and MacKenzie (1980). 相似文献
10.
Colleen George Michael T. Kopetzky Maysie J. Hughes James J. McGrath 《Research quarterly for exercise and sport》2013,84(1):25-30
Abstract Hearts from 126 male Sprague-Dawley rats (two age groups) were studied to determine effects of age, chronic hypoxia, and exercise on ventricular weight. Exercised rats had significantly heavier absolute total ventricular weights (right plus left) compared with chronically hypoxic or control rats. Whether expressed as absolute or percent total ventricular weight, chronically hypoxic rats had significantly larger right ventricles but significantly smaller left ventricles than exercised or control rats. Expressed as absolute weight, older rats (11 months) had significantly larger right or left ventricles than young rats (3 months). Expressed as percent total ventricular weight, young rats had left ventricles 4% smaller, but right ventricles 4% larger than older rats (p <.05). Type of work overload (volume or pressure) and functional location of workload (pulmonary or systemic) were suggested physiological mechanisms for stress- and age-related changes in myocardial mass. 相似文献
11.
Background:During an experiment,a ski racer equipped with various measurement devices suffered an anterior cruciate ligament(ACL)rupture in his right knee.The aim of this study was to describe the underlying injury mechanism from a functional perspective.Methods:Eight giant slalom turns(i.e.,4 left turns),followed by 1 left turn at which the ACL injury occurred,were recorded by 2 video cameras,electromyography of 4 relevant muscle groups,inertial measurement units to measure knee and hip angles,and pressure insoles to determine ground reaction forces.Results:Due to a loss of balance,the ski racer began to slide sideways at the apex of a left turn.During sliding,his right(outside)leg was actively abducted upward without touching the ground.The ski racer then attempted to stand up again by dropping his leg back towards the snow surface.The end of this dropping was accompanied by a decrease in electromyographic activity in the knee stabilizing muscles.Once the inside edge of the outer ski caught the snow surface,a rapidly increasing peak force,knee flexion,and an aggressive sudden activation of the vastus medialis muscle were observed,while biceps femoris and rectus femoris further decreased their activation levels.This likely resulted in excessive anterior translation of the tibia relative to the femur,causing damage to the ACL.Conclusion:Our example emphasizes that ski racers should not get up until they stop sliding.Remember:“When you’re down,stay down.” 相似文献
12.
Abstract Rugby players have a reduced active cervical range of motion (ACROM) mid-season compared with age-matched controls. This is most evident in rugby forwards, who have ACROM similar to patients with acute whiplash. This study aims to show if the change in ACROM over an entire rugby season (pre-, mid-, and end of season) shows a pattern of decline. A cross-sectional study of 22 rugby players (11 backs aged 24.9 ± 1.3 years; 11 forwards aged 24.5 ± 1.1 years) from elite English Premiership clubs had their cervical range of motion measured for flexion, extension, left and right side flexion, plus left and right rotation with a cervical range of motion device. The percentage change between start to mid-season, mid- to end of season, and start to end of season were calculated. Group means were compared for absolute ACROM (degrees) and percentage change over the season. The percentage change indicated a decrease in ACROM over the rugby playing season, with most of the decrement occurring in the second half of the season. Most of the relative change was observed in right lateral flexion, while rotation did not change significantly. In conclusion, ACROM declines throughout the playing season, which requires attention in terms of training and rehabilitation. 相似文献
13.
Abstract Twelve male subjects with no specialized training in sprint running were used to study effects upon the sprinter's start when hand spacing and rear knee angle were systematically altered. Results indicated that hand spacing had an effect on the start during the first 10 yd. of the sprint. The effect of rear knee angle was present at 10 yd. and the advantage gained at 10 yd. was still present at 30 yd. 相似文献
14.
BackgroundDuring an experiment, a ski racer equipped with various measurement devices suffered an anterior cruciate ligament (ACL) rupture in his right knee. The aim of this study was to describe the underlying injury mechanism from a functional perspective.MethodsEight giant slalom turns (i.e., 4 left turns), followed by 1 left turn at which the ACL injury occurred, were recorded by 2 video cameras, electromyography of 4 relevant muscle groups, inertial measurement units to measure knee and hip angles, and pressure insoles to determine ground reaction forces.ResultsDue to a loss of balance, the ski racer began to slide sideways at the apex of a left turn. During sliding, his right (outside) leg was actively abducted upward without touching the ground. The ski racer then attempted to stand up again by dropping his leg back towards the snow surface. The end of this dropping was accompanied by a decrease in electromyographic activity in the knee stabilizing muscles. Once the inside edge of the outer ski caught the snow surface, a rapidly increasing peak force, knee flexion, and an aggressive sudden activation of the vastus medialis muscle were observed, while biceps femoris and rectus femoris further decreased their activation levels. This likely resulted in excessive anterior translation of the tibia relative to the femur, causing damage to the ACL.ConclusionOur example emphasizes that ski racers should not get up until they stop sliding. Remember: “When you''re down, stay down.” 相似文献
15.
The Mechanics of Batting: Analysis of Ground Reaction Forces and Selected Lower Extremity Kinematics
Abstract The purpose of this study was to examine variations in ground reaction forces and selected lower extremity kinematics during the stride and swing phases of batting. High speed photography (100 fps) employing direct linear transformation methodology and a force plate were used to record three-dimensional kinematic and kinetic data for 7 female fast pitch softball batters. Mean vertical forces (Fz) of the right or rear foot increased to approximately 1 BW during the stride. Once the left or forward foot made contact with the ground after completion of the stride, right Fz forces decreased to .43 BW while left Fz forces rapidly increased to 1.6 BW at contact. The mean decrease in right Fz forces from peak force until contact was 55%, and the ratio of left to right Fz forces; at impact was 3.67:1. Right mediolateral forces (Fx) were exerted laterally, away from the batter, and were responsible for initiating movement of the body toward the pitched ball. As the left foot made contact with the ground at completion of the stride, left Fx forces were exerted laterally toward the pitched ball. The reaction to these forces retarded the batter's forward momentum, increased stability, and caused the left hip and knee to extend as contact approached. Right and left anteroposterior forces (Fy) acted in opposite directions (right foot pushing backward, left foot pushing forward), and were responsible for rotating the hips and upper body in a counterclockwise direction toward the pitched ball. Horizontal angular deceleration of both thighs just prior to contact was due, in part, to a decrease in these forces. These data may prove helpful when attempting to identify atypical batting patterns, and when considering improvements in shoe design. In the latter instance, force production and stability may be enhanced by aligning the cleats along the lines of action of the applied resultant shear forces. 相似文献
16.
ABSTRACTThis study examined the weightlifting load effects on the lower extremity coordination pattern during a snatch pull movement. Twenty male elite weightlifters performed snatch trials in each of the three load conditions [light (30%), medium (65%) and heavy (90%) of their maximum weightlifting capacities]. Kinematic data for the transition, second pull and take-off phases of a snatch were collected at 200 Hz using an eight-camera motion capture system. Angle-angle plots and coupling angles were calculated for further analyses. The results indicate that participants utilised knee flexion control-strategy in light and medium load conditions during the transition phase, but not for in-phase strategy in heavy load condition. In the second pull phase, participants utilised concurrent ankle dorsiflexion and knee extension, followed by hip extension strategy. The heavy load condition exhibited the distinct coordination strategies before knee extension. In the take-off phase, light and medium load conditions appeared to use thigh-phase strategy (right ankle-knee: p = 0.788, left: p = 0.035, right knee-hip: p = 0.012, left: p = 0.017, right ankle-hip: p = 0.029, left: p = 0.011). This suggests that the heavy load condition requires the use of two-joint coordination patterns (in-phase or anti-phase) as compared to the other lighter load conditions. 相似文献
17.
ABSTRACTThe purpose of this study was to investigate the effect of variations in the alignment of the feet on scrum kinetics during machine scrummaging. Twenty nine rugby forwards from amateur-level teams completed maximal scrum efforts against an instrumented scrum machine, with the feet in parallel and non-parallel positions. Three-dimensional forces, the moment about the vertical axis and sagittal plane joint angles were measured during the sustained pushing phase. There was a decrease in the magnitude of the resultant force and compression force in both of the non-parallel conditions compared to parallel and larger compression forces were associated with more extended hip and knee angles. Scrummaging with the left foot forward resulted in the lateral force being directed more towards the left and the turning moment becoming more clockwise. These directional changes were reversed when scrummaging with the right foot forward. Scrummaging with the right foot positioned ahead of the left may serve to counteract the natural clockwise wheel of the live scrum and could be used to achieve an anti-clockwise rotation of the scrum for tactical reasons. However, this would be associated with lower resultant forces and a greater lateral shear force component directed towards the right. 相似文献
18.
Alberto Fílter Jesús Olivares Alfredo Santalla Fabio Y. Nakamura Irineu Loturco Bernardo Requena 《Journal of sports sciences》2020,38(11-12):1320-1325
ABSTRACT The speed performance is involved not only in linear sprints, but also in a wide spectrum of multi-directional movements, such as curve sprinting. Curved sprint can be defined as sprint with gradual and continuous change of direction (COD). Although ~85% of the actions performed at maximum velocity in a professional soccer league are curvilinear sprints, there is not any specific test to assess this ability. This study aimed to analyse the reliability of a new curve sprint test, and compare its results with those obtained by soccer players in linear sprint. Forty experienced soccer players performed 3 attempts of curve sprint (using the penalty arc) to right and left side (17 m), and 3 linear sprints (17 m) in two different days. The ICCs (inter-session reliability) were 0.93 for sprint curve right side (CSRS) and 0.89 for sprint curve left side (CSLS), considered “acceptable”. The CVs (intra-session reliability) were 0.87% in CSRS and 1.15% in CSLS. The coefficient of determination (R2) between linear and curve sprinting was ~35%. The association between curve sides was “very large” (r = 0.878; p < 0.01). In summary, we showed that “curve sprint test” is highly reliable, and that curvilinear and linear sprints are different and independent actions. 相似文献
19.
Pedro T. Esteves Duarte Araújo Keith Davids Luís Vilar Bruno Travassos Carlos Esteves 《Journal of sports sciences》2013,31(12):1285-1293
Abstract In this study, we examined the effects of relative positioning of attacker–defender dyads to the basket on interpersonal coordination tendencies in basketball. To achieve this aim, four right-hand dominant basketball players performed in a 1 vs. 1 sub-phase, at nine different playing locations relative to the basket (from 0° to 180°, in 20° increments). Performers’ movement displacement trajectories were video-recorded and digitized in 162 trials. Results showed that interpersonal coordination tendencies changed according to the scaling of the relative position of performers to the basket. Stable in-phase modes of coordination were observed between performers’ longitudinal and lateral displacements (50.47% and 43.02%) on the left side of the court. On the right side of the court, a shift in the dominant mode of coordination was observed to a defender lead-lag of ?30°, both for longitudinal and lateral displacements (30.51% and 32.65%). These results suggest how information about dribbler hand dominance and relative position to the basket may have constrained attacker–defender coordination tendencies in 1 vs. 1 sub-phases of basketball. 相似文献
20.